Thanks for posting and welcome to the Bose Community Forums.
I am sorry, but the buds are designed to work as a pair and as such, a replacement cannot pair with the existing. For this reason, we do not sell individual buds. The best option here would be to reach out to your local customer support center and explore the service options for your headset. You can do this by clicking this link here, selecting your region, scrolling to the bottom of the page, and selecting contact us. If you are in the US or UK you can also reach out via Facebook or Twitter and one of our team can help you there. Or you can book in an exchange on the UK or US website by selecting the option under the 'Support Tab'.
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